Container having corner post for top to bottom stacking



United States Patent [72] Inventor [54] CONTAINER HAVING CORNER POST FOR TOP 3,116,867 l/1964 Morgan 229/34 3,286,901 11/1966 Anderson 229/34X FOREIGN PATENTS 556,550 2/1957 Italy 229/(S) 483,866 6/1952 Canada 229/34 971,565 9/1964 Great Britain.... 229/34 501,922 3/1939 Great Britain.... 229/34 615,354 6/1961 Italy 229/34 Primary ExaminerJoseph R. Leclair Assistant ExaminerSteven E. Lipman Attorney-Carpenter, Ostis & Lindberg ABSTRACT: A self-locking container formed from a unitary blank of paper board and characterized by a bottom panel with side and end panels connected to the bottom panel, the ends of the side panels having fold-in flaps extending along the inside of the end panels, each end panel being coextensive with a top panel which when folded into position is coplanar with the top edges of the side and end panels, each top panel having at each end thereof a corner post member capable of being folded along a score line and when in position at the folded juncture of the side panels and flaps thereof providing stiffening of the container. The lower ends of the corner post member may be arranged to enter slots or cut and crushed scores in the bottom panel. The top panels provide good stacking of the container.

A 3L645L666 PATENTEU DEC 8 I970 SHEET 2 OF 2 m mvrofi PRANAS V/SVYDAS CONTAINER HAVING CORNER POST FOR T]? TO BOTTOM STACKING BACKGROUND OF THE INVENTION SUMMARY OF THE INVENTION The structure according to the present invention comprehends a corner post for a self-locking container, said corner post having elements flanking both the side and end panels and having bearing contact with a top panel and the bottom panel of the container, to the end that the container has good stacking properties.

DRAWINGS FIG. 1 shows a unitary cut and scored paperboard blank for forming into a container according to the present invention;

FIG. 2 is an isometric view showing some of the steps in setting up the container;

FIG. 3 is a vertical section taken along the line 3-3 of FIG. 2 looking in the direction of the arrows;

FIG. 4 is a horizontal section taken along the line 4-4 of FIG. 2 looking in the direction of the arrows;

FIG. 5 is an isometric view of the container with the closure flap thereof in position;

FIG. 6 is a vertical section taken essentially along the line 6-6 of FIG. 5 looking'in the direction of the arrows; and

FIG. 7 is a vertical section taken along the line 77 of FIG. 5 looking in the direction of the arrows.

A unitary blank of paperboard or similar material for forming the container according to the present invention is denoted by the reference numeral 10 and comprises a bottom panel 11, opposed side panels 12 foldably connected to bottom panel 11 along score lines 13. Opposed end panels 14 are foldably connected to bottom panel 11 along score lines 16.

Each of the side panels 12 is provided at the ends thereof with flaps 17 foldably connected thereto along score lines 18. Flaps 17 are adapted to be folded at right angles to side panels 12 along the inside of the end panels 14 when the latter are folded to erect position.

End panels 14 are each provided with a top panel 21 hingedly attached thereto along a score line 22. Each end of the top panels 21 has a corner post extension 23 therefrom, the latter including a side element 27 foldably connected to top panel 21 along a score line 24. An end element 26 is hingedly attached to a side edge of element 27 along a score line 28 and extends downward adjacent the inside of a related side panel flap 17.

Elements 26 and 27 provide structure for lending stiffness to the corners of the container as well as good stacking qualities. Moreover, elements 26 and 27 provide additional support for the top panel 21 when the same is in the setup position seen in the several views.

In the setup position of the container, element 26 is adapted to stand along the flap 17 of sidewall 12, while element 27 is adapted to stand along the inner face of sidewall 12, as seen more particularly in FIG. 4.

Structure is provided for locking element 26 in position if desired, and to this end the bottom panel 11 may be scored and crushed as at 32 and 33, (commonly known as a Walker Lock) at the comers thereof, while element 26 is provided with a locking tab 31 adapted to be in locking engagement with Walker Lock 32.

It will be seen from the description thus far, that the elements 26 and 27, together with the side panel 12 and the flaps 17 thereof, provide extra thickness layers at the corner of the container. By reason of element 27 having good bearing against bottom panel 11, and element 26 having good bearing both against bottom panel 11 and against the underside of top panel 21, good vertical stiffness is provided.

Top panel 21 also enables the container to be stacked one atop another. Ifdesired, the container may be open-topped for display of the contents thereof. If desired, however, it can be provided with a top closure panel 36 foldably connected by a fold line 37 to one of the side panels 12. A tuck-in flap 38 is foldably connected along a fold line 39 to closure panel 36.

I claim:

1. A self-locking container formed from a unitary blank of foldable paperboard and including a bottom panel, opposed side panels and opposed end panels folded to upstanding position along score lines at the edges of said bottom panel:

a. said opposed side panels having flaps hingedly attached at the ends thereof and folded inwardly at right angles thereto against the inside of their corresponding end panels; said opposed end panels each having a top panel hingedly attached and folded inwardly from the upper edge thereof into a position substantially coplanar with the top edges of said side and end panels;

c. each of said top panels having at each end thereof a corner post member comprising:

i. a side element hingedly attached to the side edge of said top panel and extending downwardly along the inside of a related sidewall;

ii. an end element hingedly attached to a side edge of said side element and extending downwardly adjacent the inside of a related side panel flap;

d. each of said elements extending the entire distance between said top and bottom panels and providing a comer post for support of said top panel and stacking strength of said container.

e. each of said end elements being provided with locking means at the lower end thereof engageable with said bottom panel for holding said flaps and said panel in position.

2. A self-locking container according to claim 1, wherein said bottom panel is provided with an opening for reception of the lower end of said end element to lock the latter to said bottom panel.

3. A self-locking container according to claim 1, wherein said bottom panel is scored and crushed in the corners thereof for reception of the lower end of said end element to lock the latter to said bottom panel.

4. A self-locking container according to claim 3, where said end element has a locking tab extending therefrom adapted to be received in the scored and crushed corners of said bottom panel.

5. A self-locking container according to claim 1, wherein at least one of said elements has the upper and lower extremities thereof in bearing contact with the underside of said top panel and the said bottom panel. 

